3.0.0 preview 2 Razor Components: "InputFormatters" is empty when making Web API POST #7438
Description
With a new "Razor Components" project using .NET Core 3.0.0 preview 2, I am trying to make an Http call to a controller on the server to save game data to a SQLite database. But, any POST call that I to do to a controller method with a [FromBody] parameter attribute, I get the following error: `System.InvalidOperationException: 'Microsoft.AspNetCore.Mvc.MvcOptions.InputFormatters' must not be empty. At least one 'Microsoft.AspNetCore.Mvc.Formatters.IInputFormatter' is required to bind from the body.
I see that a JsonInputFormatter should be included by default when I register the MVC services, but for some reason there are no InputFormatters in the context.
To test this, I created a brand new Razor Components project under .NET Core 3.0.0 templates.
I registered MVC and HttpClient services on my Server.Startup class:
public class Startup
{
// This method gets called by the runtime. Use this method to add services to the container.
// For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
public void ConfigureServices(IServiceCollection services)
{
services.AddMvc();
if (!services.Any(x => x.ServiceType == typeof(HttpClient)))
{
// Setup HttpClient for server side in a client side compatible fashion
services.AddScoped<HttpClient>(s =>
{
// Creating the URI helper needs to wait until the JS Runtime is initialized, so defer it.
var uriHelper = s.GetRequiredService<IUriHelper>();
return new HttpClient
{
BaseAddress = new Uri(uriHelper.GetBaseUri())
};
});
}
services.AddRazorComponents<App.Startup>();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
};
app.UseMvc();
app.UseStaticFiles();
app.UseRazorComponents<App.Startup>();
}
}
I created a CounterController class on my Server with a simple test method:
public class CounterController : Controller
{
[HttpPost]
[Route("/api/Counter/Test")]
public void Test([FromBody]string value)
{
var test = value;
}
}
And updated the Counter.cshtml file to inject the Httpclient and make a call to our controller:
@page "/counter"
@using System.Net.Http;
@inject HttpClient Client
<h1>Counter</h1>
<p>Current count: @currentCount</p>
<button class="btn btn-primary" onclick="@IncrementCount">Click me</button>
@functions {
int currentCount = 0;
void IncrementCount()
{
currentCount++;
var stringReq = new StringBody() { value = "test" };
Client.PostJsonAsync("/api/Counter/Test", stringReq).Wait();
}
public class StringBody
{
public string value { get; set; }
}
}
I can use [FromQuery] parameters and everything works fine, but I just cannot get sending JSON to work because of this error. I verified that the request is being made with the correct content type and the body is valid JSON. I'm also learning Blazor as I go here and don't have a solid background with MVC/Razor pages, so it's very possible I'm just doing something wrong. My goal is to have a web game that can persist game data to a database on the server. I figured I would have my EF dbcontext datalayer and my web api controller living on the server to accept client calls for saving/updating game state.
Full stacktrace:
System.InvalidOperationException: 'Microsoft.AspNetCore.Mvc.MvcOptions.InputFormatters' must not be empty. At least one 'Microsoft.AspNetCore.Mvc.Formatters.IInputFormatter' is required to bind from the body.
at Microsoft.AspNetCore.Mvc.ModelBinding.Binders.BodyModelBinderProvider.GetBinder(ModelBinderProviderContext context)
at Microsoft.AspNetCore.Mvc.ModelBinding.ModelBinderFactory.CreateBinderCoreUncached(DefaultModelBinderProviderContext providerContext, Object token)
at Microsoft.AspNetCore.Mvc.ModelBinding.ModelBinderFactory.CreateBinder(ModelBinderFactoryContext context)
at Microsoft.AspNetCore.Mvc.Controllers.ControllerBinderDelegateProvider.GetParameterBindingInfo(IModelBinderFactory modelBinderFactory, IModelMetadataProvider modelMetadataProvider, ControllerActionDescriptor actionDescriptor, MvcOptions mvcOptions)
at Microsoft.AspNetCore.Mvc.Controllers.ControllerBinderDelegateProvider.CreateBinderDelegate(ParameterBinder parameterBinder, IModelBinderFactory modelBinderFactory, IModelMetadataProvider modelMetadataProvider, ControllerActionDescriptor actionDescriptor, MvcOptions mvcOptions)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvokerCache.GetCachedResult(ControllerContext controllerContext)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvokerProvider.OnProvidersExecuting(ActionInvokerProviderContext context)
at Microsoft.AspNetCore.Mvc.Infrastructure.ActionInvokerFactory.CreateInvoker(ActionContext actionContext)
at Microsoft.AspNetCore.Mvc.Routing.MvcEndpointDataSource.<>c__DisplayClass22_0.<CreateEndpoint>b__0(HttpContext context)
at Microsoft.AspNetCore.Routing.EndpointMiddleware.Invoke(HttpContext httpContext)
at Microsoft.AspNetCore.Routing.EndpointRoutingMiddleware.Invoke(HttpContext httpContext)
at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)